1. Field of the Invention
This invention relates generally to occupancy status monitoring and signaling systems.
2. Description of the Related Art
In many work environments, the occupancy of tall cubicles and enclosed offices cannot be ascertained from a distance. A person looking for the occupant of a cubicle or an office must walk to the cubicle or office to see if the occupant is there. Time is wasted and frustration is induced when the person being sought is not in the cubicle or office. Also, no means is usually available for announcing the wish not to be disturbed or for indicating, when leaving the workspace, whether the absence will be for a short or a long duration. Most importantly, no means is commonly available by which a person may request help when experiencing a medical emergency or when being threatened with physical harm.
Various devices for indicating occupancy in a room are known but they typically lack the ability to distinguish between random and directional motion and between a moving person and a stationary one. U.S. Pat. No. 5,861,806 to Vories et al. discloses an indicator that automatically indicates whether a room is occupied or not. However, it is designed for a limited-use space such as a restroom and cannot detect emergencies or register temporary absences or the desire to be undisturbed. U.S. Pat. No. 5,717,867 to Wynn et al. discloses a time entry and accounting system activated by individually encoded identification cards presented to computerized time clocks adjacent to employee workstations. The time clocks include screens for displaying messages from the central computer and buttons for sending information to the computer. However, the system does not monitor each workspace and automatically detect and indicate an employee""s presence, absence or the occurrence of an emergency. U.S. Pat. No. 5,703,367 to Hashimoto et al. discloses a method for estimating the ratio of human occupancy in a restricted space. However, it is designed for monitoring the usage of high traffic areas, such as elevator lobbies and meeting rooms, and not for indicating the occupancy of workspaces. Consequently, it does not provide xe2x80x9cDo not disturb,xe2x80x9d absence or emergency indications. U.S. Pat. No. 4,679,034 to Kamada discloses a device for detecting the presence of a human body in a sensing zone and generating audio and visual displays. However, it is intended as an intrusion alarm and does not monitor occupancy status under normal working conditions or provide for a multiplicity of displays. U.S. Pat. No. 4,476,461 to Carubia discloses an occupancy indicator that utilizes switches for monitoring occupancy in remote locations. Signals from the switches are transmitted to an occupancy information recorder through a communication circuit. However, the indicator does not include automatic detection of occupancy, absences, emergencies, or status displays at the locations being monitored. U.S. Pat. No. 4,340,879 to Laflamme shows a manually operated device featuring a plurality of indicators to register whether a person is in or out on a display in a reception area. However, no provision is made for automatic monitoring or for displaying occupancy status at each workstation. U.S. Pat. No. 3,964,058 to Winston shows a lighted xe2x80x9cDo not disturbxe2x80x9d sign which, is manually operated. It is designed for domestic use and does not provide automatic detection of occupancy, absences or emergencies.
An occupancy status indicator, according to the invention, comprises a motion detector, an indicator, and a controller, to which both the motion detector and the indicator are connected. The motion detector is adapted to send a signal when it detects motion in a space and when it detects the presence of a person in the space. The indicator displays information about the occupancy of the space, and the controller receives signals from the motion detector and activates the indicator. The controller will activate the indicator to display a first condition when the motion detector signals motion in the space and the presence of a person in the space, said motion and presence being a first status of occupancy. The controller will activate the indicator to display a second condition when no motion is detected in the space and the motion detector signals the presence of a person in the space, said presence and lack of motion being a second status of occupancy. The controller will activate the indicator to display a third condition when no motion is detected in the space and no person is detected in the space, said lack of motion and lack of presence being a third status of occupancy.
Preferably, the motion detector is a passive infrared sensor. The controller may be a dedicated component or a computer. Preferably, the indicator is a visual display, comprising three lights. Typically, the three lights will be red, amber, and green, where the green light indicates the first status of occupancy, the red light indicates the second status of occupancy, and the amber light indicates the third status of occupancy.
In one aspect of the invention, the visual display of occupancy status appears on a computer screen. In yet another aspect in the invention, the controller is connected to a communications network, allowing the indications of status to be sent to selected remote locations that are connected to said communications network. Additionally, a silent alert may be sent to selected remote locations by use of a concealed switch also connected to said controller.
In one aspect of the invention, the indicator is mounted on a cubicle defming the space. It may be that the space is partially enclosed and accessible by an entryway where the motion detector is positioned to detect the direction of motion through the entryway. In another aspect of the invention, either the controller or the motion detector can determine when no motion exists. This is typically done by sensing a predetermined period of a lapsed time from the last motion signal.
The indicator can be either a visual display or an audio display, or some combination of both. If audio, the preferable display is a beeper. The invention also contemplates the controller having a component, manually operable, to activate the indicator and to replicate its display.
Additionally, the system may control the working lights and office machines in the cubicle or office as an energy saving strategy.